gives place to the formation of septate, V-shaped, and
"branched forms. It seems to be normally a strepto-ba-
cillus in its early stages, but eventually becomes very
pleomorphous, varying in appearance from a chain of
oval cocci to the hypha of the moulds. There seems to
be nothing peculiar about the staining-capacity of the
bacillus. It stains with the ordinary solutions of the
anilin dyes, retains the stain of Gram's method, and is
decolorized by mineral acids.
Dohle* succeeded in staining certain protoplasmic
bodies in the tissues in syphilis, which resembled the
actively motile protoplasmic bodies which he had pre-
viously encountered in the discharges. They were for
the most part round or oval, sometimes with irregular
outlines, and were provided with flagella. The staining
took place in a mixture of hematoxylon and carbol-fuch-
sin, subsequently treated with iodin or chromatin, and
washed in alcohol.
Convinced that these bodies were the cause of syphilis,
he excised small fragments from gummata and other
syphilitic tissues, and placed them beneath the skin of
guinea-pigs, which subsequently fell ill with a chronic
marasums which ultimately caused death.
In the inoculation experiments of van Niessen there
were observed as evidences of the specificity of the
organism discovered by him: (i) abortion in pregnant
female rabbits; (2) extra-genital primary lesions on the
ears of inoculated rabbits in the form of nodes; (3) sec-
ondary ulcer and tumor formations, and irregular lesions,
such as occasional thrombosis and pneumonia.
1 Munch, med. Wochenschrift, 1897, No. 43.